We will focus first on the mechanisms and "metabolic logic" that support "training on an empty stomach, distinguishing what is" advisable to do "from what" could "and finally what should be" avoided ".
general thanks to the use of energy sources of muscle, liver and fat deposits.Those caloric, based stocks creatine-phosphate, glycogen and triglycerides, are continually demolished and replaced. The "animal is therefore able to" empty and fill "in a way that we would define perfectly" normal "- even if this potential depends very much on the species in question.
If we think about it, for the wild animal it is precisely in the absence of nutritional substrates that the "organism" must be able to become more active. Hunting by running, climbing, walking long and digging are in fact activities that require the global recruitment of the locomotor system. even considerably.
For further information: Intermittent Fasting consumed in fasting or in effort, allowing to save energy reserves.
In the long run this can even promote muscle depletion "reducing general consumption" during the activity, to the advantage of "further saving of caloric substrates - a bit" as if "horsepower is removed from the engine".
If you have read carefully, you will have already guessed that metabolic efficiency is the worst enemy of the Western man who would like to lose weight and grow muscle. This because:
- For decrease in fat mass it is necessary to catabolize as many fat reserves as possible, while ensuring all essential non-energy nutrients;
- For gain muscle mass it is necessary on the one hand to prevent the contractile tissues from being damaged (catabolism for energy purposes), and on the other to promote the anabolic construction of the same.
What to do to reduce metabolic efficiency
In the long term, to decrease metabolic efficiency and "deceive" the body into believing that it is not necessary to accumulate fat reserves but, on the contrary, that it is essential to grow muscles, it is essential:
- Always eat a little more (hyper-) than necessary to remain stable with weight (normo-);
- Do not neglect the intake of carbohydrates, substantially useful for saving muscle, making it grow and keeping the metabolism high;
- Training "in the round", without neglecting aerobic, metabolic and obviously muscle strengthening activities.
But, what happens after having faced a fast, perhaps having trained and, finally, having conquered the meal?
in order to eat, the body finally has the task of managing the nutrients it derives from it.The "how it handles them" is defined "(metabolic) ability to manage energy nutrients"For a sportsman or for those looking for a body recomposition, obviously, this will have to prefer the muscular destination to the adipose one.
Do not make the mistake of confusing this ability with the metabolic survival efficiency described in the previous paragraph. Here we talk about the preference of using glucose and amino acids gained with the meal, following fasting and probably after a certain physical workload.
We start from the assumption that following fasting and physical motor activity of any kind - such as physical exercise - physiologically the body demonstrates a high predisposition to intelligently use what it eats.
We speak of "intelligence", but we mean "logic". Yes, because it is natural to give priority to muscle tissue and the liver (for the reserves of glycogen and contractile proteins), since they are essential to maintain brain work (liver glycogen) and ad perform actions hunting, gathering, walking and climbing (glycogen of the muscles and contractile proteins of the same). Without it, it would not be possible to feed later.
However, all carbohydrates and proteins that remain, and obviously almost all of the fats present in the meal (since they cannot be used to fill glycogen stores or to repair muscles), are destined for adipose tissue.
From here it is possible to understand the reason for maintaining a low lipid percentage in HYPER-calorie diets aimed at muscle growth. But that's another topic.
But how can all this happen? Who is the "puppeteer" who manipulates the metabolic capacity to manage nutrients? The "whole", understood as the homeostatic capacity of the organism.
We therefore limit ourselves to emphasizing the "importance of the" message "and" who receives it. "We are talking about hormones and neurotransmitters in the first case, and specific tissue receptors in the second.
The topic is vast. On the other hand, almost all of the messengers are almost impossible to manage, as is the mapping and sensitivity of specific tissue receptors. This with few exceptions, the most important of which is that of glucose metabolism and related insulin action on tissues.
Fasting and training improve the ability of the liver and muscles to receive glucose, then transform it into glycogen, and to repair damaged contractile tissue (anabolic capacity). This happens for the optimization of the insulin work, intended as secretion and peripheral reception of the hormone.
If the physical workload has been significant and the meal is eaten immediately afterwards, a greater insulin-independent sensitivity is also established in the muscles.
C "it must also be said that by often performing a" muscular activity with a workload such as to use mainly glucose - training with a "metabolic" component - it is possible to increase his insulin sensitivity. Conversely, a sedentary lifestyle and overweight (excess adipose) decrease it.
This is all very important. In fact, consuming too abundant meals without having fasted before or having practiced physical exercise, both energy molecules and insulin accumulate, favoring the synthesis of fatty acids and their storage in adipose tissue. This circumstance "makes you fat" when it occurs, but it also creates a certain "worsening" attitude in the chronic.
Therefore, having a glycogen deficiency in the liver and muscles, and a greater receptor sensitivity due to training, is the "key" to enjoy optimal post-workout and / or post-fast recovery.
, from physiology to nutritional strategies, from biological rhythms to correct biomechanics, we should take into account "biological" intelligence, or rather the aforementioned evolutionary logic.
We "move" driven by the sense of hunger, a physiological survival impulse mediated by neurotransmitters and hormones that interact passing from one tissue to another.
Hunger is higher when the digestive tract is empty, when the fatty tissue is "deflated", when the blood sugar drops.
The biological rhythms that characterize living beings, including appetite-satiety, are encoded for a very evident reason: individual survival. But is that still the case today?
- No, since a sedentary lifestyle and overeating lead to a reduction in life expectancy.
- Or yes, because it is natural to overfeed and move as little as possible, in anticipation of the famines that have characterized the entire human history - with the exception of the last few decades, and not even all over the world.
In fact, we don't know. As usual, the concept of "naturalness" is in contrast with what is the normal lifestyle of the modern Western or Westernized animal-man, who eats not because he has a real organic need, but rather because of the " biochemical influence of nervous stress, incorrect behavioral habits, metabolic complications, etc.
All this leads us to reflect on a crucial point: Do I move to eat or do I eat to move?
of fabrics, inserted in a context of natural rhythms not distorted by "modern confusion".But are we sure it's that simple? So immediate and intuitive? Obviously not.
What training to practice, for how long, for whom and with what intensity? Questions that "undermine the foundations" of what is stated in the first lines of this paragraph.
An error of assessment would therefore make "training on an empty stomach" unnatural "or, more concretely, unproductive.
How is fasting training structured?
Let's start by specifying right away that, to train on an empty stomach, one must naturally be predisposed to do so and / or progressively train the specific tolerance to it.
Fasting is to be avoided in case of low blood pressure, tendency to hypoglycemia, anemia, various diseases or compromised health status.
On the other hand, many claim to train better on an empty stomach. This is probably because their central nervous system is more lucid under the action of GH, a normally anabolic hormone which however also acts as a hyperglycemic agent in the case of physical exercise, rather than with high blood sugar and insulin typical of the post-prandial. For others it may work the other way around.
It is also probable, however, that they have "a" limited autonomy ", 45-50" at the most; an "hour would already be very challenging to reach.
That said, even the toughest of us would sooner or later succumb to fatigue. Because? Let's see it.
Types of Workout: Which Is Best Fasting?
The various forms of training (with the exception of specific sessions, for example for flexibility) could be classified into one of the four categories below:
- HVT: aerobic, low or medium intensity, high volume;
- Aerobic and continuous, with high intensity rhythm variations (HIT) - above anaerobic threshold - at medium volume;
- Metabolic HIIT: lactic acid anaerobic, high intensity, interspersed but with high density, low volume;
- HIIT for hypertrophy: anaerobic alactacid and lactacid, high intensity (about 75-85% 1RM), interspersed but with medium density and medium-low volume.
- HIIT of speed or strength: anaerobic alactacid and only marginally lactacid, at very high intensity (> 85% 1 RM), interspersed but with low density and low volume.
When fasted, however, not all of these workouts are "feasible" or effective.
Let's take high-volume activities for example. They have the highest energy cost per session and, if fasted, jeopardize the integrity of contractile proteins.
On the other hand, high intensity activities require full performance capacity. If the central nervous system goes into "crisis", even boasting full reserves of muscle phosphates and glycogen, it becomes impossible to express the top of strength or speed.
We can therefore understand that what makes the difference is above all the overall load. When fasted it must be lower than in the post-prandial meal.
The workload is given by volume, intensity and density. But for certain workouts, high intensity is essential; without it it would be useless. Same goes for density in lactacid metabolic work and for above-threshold aerobic disciplines. Here perhaps the most easily manageable parameter is volume.
The preferable time is the one in the morning as soon as you wake up, for obvious reasons (physiological fasting of at least 10 hours). Some followers of the "now known" intermittent fasting "however, manage to organize the routines at other times of the day.
it is reduced compared to the day, when we are active, but in any case the consumption of basal oxygen remains such as to require the recruitment of deposits to support nocturnal activity.
Everything is strictly dependent on the last meal of the evening and above all on its composition in carbohydrates, fats and proteins.
If we consider that on average, in official nutrition, it is recommended to remain "on average light" for dinner compared to lunch, the condition is created whereby, after about 2-3 hours, the need to eat would return. Wanting to lose weight, you should of course resist! It is different for those who intend to grow muscle.
Organs such as the brain, heart, liver and lungs, and all systems in the body, use oxygen even when we sleep. In physiological conditions of rest, the body gets its energy from a mixture of fats and carbohydrates. The lower the heart rate, the higher the percentage consumption of lipids. It is estimated that on average, in basal conditions, one is consumed energy mixture given by about 50-70% of fats and 30-50% of carbohydrates - perfect condition for weight loss.
If it is true that after a few hours from the last meal the body has no more food to use, how does it sustain itself during the night's rest? As for the fat there are no problems, while the point is placed on glucose.
Under the effect of glucagon, even during the night, the liver keeps blood sugar constant releasing glucose from glycogen. So, having a light dinner at 20:30, an appetite would come by as early as 10:30 pm. At about 11 pm you will go to sleep and throughout the night your blood sugar will be supported by hepatic glycogenolysis. In the morning at 7:00, after waking up, you could then organize a fasting workout (7:30).
We are talking about a 10 and 30 hour fast "; trust the kind readers if I say that, especially when the last supper is low in carbohydrates, training in these conditions is almost unthinkable.So, if you train after 10-11 hours of fasting, dinner must provide at least 40% of the calories (against 35% normally recommended) and some of which must come from carbohydrates.
For those who succeed in the intent ... what is the advantage? None. Or rather, there is undoubtedly a greater consumption of fatty acids during any aerobic session or post-workout for those who train in HIT. However, the "organism" is not stupid "and reacts by increasing the fat deposit at the following meal.
There is to be said that fasting training, as well as intermittent fasting, give excellent results in people who have problems with hyperglycemia and hypertriglyceridemia. We therefore recommend it for the control of uncomplicated dysmetabolic pathologies or which allow training under medical monitoring.
The ability to manage subsequent dietary carbohydrates will be maximal; but this would also have happened at other times.
The actual weight loss actually took place during the night. The fact of having trained immediately afterwards does not have a real impact, on balance, on the goal of weight loss. really important training loads.
and of the major energy debt given by fasting, protein synthesis will increase exponentially - as the muscle will inexorably suffer from fasting training, despite having the utmost care in load management - as will glycogenosynthesis.All this, provided that you try to structure "clean" and calibrated meals, which respect any caloric deficit necessary for weight loss. Green light to food supplements, but only when necessary, and to foods with a high calorie density such as cereals and seeds oily, as well as foods with high protein content and high biological value (milk, yogurt, cheeses and lean ricotta, eggs, lean meat and fish, etc.).
